Andrew Morton wrote:

On Sun, 16 Dec 2007 15:10:14 -0500 "Miles Lane" [off-list ref] wrote:

quoted

On Dec 16, 2007 3:19 AM, Herbert Xu [off-list ref] wrote:

quoted

On Sat, Dec 15, 2007 at 11:56:04PM -0800, Andrew Morton wrote:

quoted

On Sun, 16 Dec 2007 01:37:01 -0500 "Miles Lane" [off-list ref] wrote:

quoted

quoted

On Sun, Dec 16, 2007 at 11:07:07AM +0800, Herbert Xu wrote:

So I posted this patch after 19:00 PST on 15 Dec.

quoted

quoted

Dec 15 13:44:39 syntropy kernel:  #0:  (&p->lock){--..}, at:
[crypto_algapi:seq_read+0x25/0x191c1] seq_read+0x25/0x26f

So your kernel is still feeding garbage into lockdep.

Are you really really sure that kernel had Herbert's patch applied?

The above log message is stamped as 13:44 PST.  I gotta say
this doesn't look good :)

Yes, I did have the patch applied, but I had reenabled LOCKDEP_DEBUG.
I just tried with the LOCKDEP_DEBUG stuff turned off, and with this
configuration, the problem is resolved.  It seems that the patch
you made does fix the problem with /proc/net/packet. This new issue
seems to be a different problem.

So, I tried building another kernel with LOCKDEP enabled (.config attached):
With this kernel, I got:

Dec 16 11:21:39 syntropy kernel: [  278.723108] process `tail' is using deprecated sysctl (syscall) net.ipv6.neigh.default.retrans_time; Use net.ipv6.neigh.default.retrans_time_ms instead.
Dec 16 11:21:40 syntropy kernel: [  279.226103] in_atomic():1, irqs_disabled():0
Dec 16 11:21:40 syntropy kernel: [  279.226106] no locks held by tail/6208.
Dec 16 11:21:40 syntropy kernel: [  279.226109] Pid: 6208, comm: tail Not tainted 2.6.24-rc5-mm1 #5
Dec 16 11:21:40 syntropy kernel: [  279.226112] [show_trace_log_lvl+0x12/0x25] show_trace_log_lvl+0x12/0x25
Dec 16 11:21:40 syntropy kernel: [  279.226121] [show_trace+0xd/0x10] show_trace+0xd/0x10
Dec 16 11:21:40 syntropy kernel: [  279.226126] [sbp2:dump_stack+0x57/0x17c1] dump_stack+0x57/0x5f
Dec 16 11:21:40 syntropy kernel: [  279.226130] [firewire_core:__might_sleep+0xd7/0x29a] __might_sleep+0xd7/0xde
Dec 16 11:21:40 syntropy kernel: [  279.226136] [parport:copy_to_user+0x32/0xd13f] copy_to_user+0x32/0x47
Dec 16 11:21:40 syntropy kernel: [  279.226141] [add_to_pagemap+0x29/0x56] add_to_pagemap+0x29/0x56
Dec 16 11:21:40 syntropy kernel: [  279.226147] [pagemap_pte_range+0x74/0xb1] pagemap_pte_range+0x74/0xb1
Dec 16 11:21:40 syntropy kernel: [  279.226151] [walk_page_range+0x115/0x1dc] walk_page_range+0x115/0x1dc
Dec 16 11:21:40 syntropy kernel: [  279.226157] [pagemap_read+0x154/0x1e8] pagemap_read+0x154/0x1e8
Dec 16 11:21:40 syntropy kernel: [  279.226161] [vfs_read+0xa2/0x11e] vfs_read+0xa2/0x11e
Dec 16 11:21:40 syntropy kernel: [  279.226166] [sys_read+0x3b/0x60] sys_read+0x3b/0x60
Dec 16 11:21:40 syntropy kernel: [  279.226170] [sysenter_past_esp+0x6b/0xc1] sysenter_past_esp+0x6b/0xc1

Yes, this is a different bug - the pagemap stuff is doing userspace access under kmap_atomic() - we discovered this a couple of days ago and Matt has been informed.

It's relatively harmless and if that's the only problem you're observing then I think we're OK here.

Hello, is this the same BUG?  If so, it is still hanging around in 2.6.24-rc6-mm1.
FWIW, I reproduced this problem on a different machine this time.  This new trace is from an "AMD Athlon(tm) XP 2500+ stepping 00" machine with an NVidia chipset.

I hope this helps,
        Miles

Dec 27 10:44:48 PenetratingVision kernel: [ 3780.832218] process `tail' is using deprecated sysctl (syscall) net.ipv6.neigh.default.retrans_time; U
se net.ipv6.neigh.default.retrans_time_ms instead.
Dec 27 10:44:48 PenetratingVision kernel: [ 3780.974877] printk: 16 messages suppressed.
Dec 27 10:44:48 PenetratingVision kernel: [ 3780.974885] wlan0_rename: RX non-WEP frame, but expected encryption
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617218] BUG: sleeping function called from invalid context at include/asm/uaccess_32.h:457
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617228] in_atomic():1, irqs_disabled():0
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617231] no locks held by tail/6407.
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617235] Pid: 6407, comm: tail Not tainted 2.6.24-rc6-mm1 #3
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617239]  [show_trace_log_lvl+0x12/0x25] show_trace_log_lvl+0x12/0x25
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617252]  [show_trace+0xd/0x10] show_trace+0xd/0x10
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617257]  [sbp2:dump_stack+0x57/0x17bf] dump_stack+0x57/0x5f
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617263]  [parport:__might_sleep+0xd7/0x1e96] __might_sleep+0xd7/0xde
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617272]  [usbcore:copy_to_user+0x32/0x44e] copy_to_user+0x32/0x49
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617281]  [add_to_pagemap+0x29/0x56] add_to_pagemap+0x29/0x56
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617289]  [pagemap_pte_range+0x74/0xb1] pagemap_pte_range+0x74/0xb1
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617294]  [walk_page_range+0x115/0x1dc] walk_page_range+0x115/0x1dc
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617301]  [pagemap_read+0x154/0x1e5] pagemap_read+0x154/0x1e5
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617306]  [vfs_read+0xa2/0x11e] vfs_read+0xa2/0x11e
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617313]  [sys_read+0x3b/0x60] sys_read+0x3b/0x60
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617317]  [sysenter_past_esp+0x6d/0xc5] sysenter_past_esp+0x6d/0xc5
Dec 27 10:44:49 PenetratingVision kernel: [ 3781.617322]  =======================